Preparing for Resilient PNT Standards: Conducting a PNT Vulnerability and Risk Assessment

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With new technical standards for resilient PNT on their way, our latest webinar explores how to assess the risks arising from natural and manmade threats to PNT systems.

The world is waking up to the need to secure the positioning, navigation and timing (PNT) systems that lie at the heart of much of our critical infrastructure.

From high-speed trains to cellular telecoms networks, much of the infrastructure we use every day relies on PNT sensors and systems that tell it exactly where it is and precisely what time it is. If those sensors or systems are compromised, the infrastructure as a whole can fail.

As examples, look at the US container port that was put out of action for several hours in 2014 by suspected GPS jamming, or the AirAsiaX flight from Sydney to Kuala Lumpur in 2015, where a user input error caused navigation systems to shut down, forcing the plane to divert to Melbourne.

Incidents like these are on the rise, and are spurring efforts to develop technical standards to ensure the resilience of PNT systems in the face of a diverse array of threats.

The work of defining those standards is now underway at the IEEE, and our latest webinar series, Implementing Resilient PNT in the Real World, explores how developers and users of critical PNT systems can start preparing for them today.

How to assess PNT system vulnerabilities

The second webinar in the series looks at how organisations can assess the operational and financial risks arising from compromised PNT systems.

Presented by Dana Goward, President of the Resilient Navigation and Timing Foundation, and Guy Buesnel, Spirent’s PNT Security Technologist, it provides expert advice on categorising the threats to PNT systems, assessing a system’s vulnerability to those threats, and conducting a risk analysis in terms of safety of life, operational performance and financial exposure.

Guy explains the complexities of assessing the risks to safety-critical and liability-critical PNT systems that use multiple sensors to compute and maintain an accurate position. The vulnerabilities of those sensors must be understood both individually and at a system-of-systems level, and testbeds must be able to test their resilience likewise.

The challenges of testing and measuring system resilience are also covered. Given that threats to PNT systems can vary enormously, and the way systems respond to threats is highly dependent on specific conditions at the time of the incident, what is the best way to approach testing? Guy provides some pointers that will be explored further in the third webinar in the series: A Proposed Test Framework for Robust PNT.

How to analyse and quantify risk for PNT-dependent systems

In his presentation, Dana Goward offers a practical framework for understanding, categorising and quantifying the risks to PNT systems that use global navigation satellite systems (GNSS) like GPS as a sensor input.

He outlines more than 20 threat vectors that can disrupt GNSS-based systems, from natural phenomena like solar storms to deliberate jamming or spoofing of RF signals, and the growing possibility of state-sponsored attacks on navigation satellites in space.

His framework enables developers and users of PNT systems to assess which vectors present the greatest threat to those systems and what the likely operational and financial impact of an incident would be.

While aimed primarily at developers and users, the framework should also be of interest to policymakers exploring ways to protect critical national infrastructure, and insurers interested in understanding the fast-evolving risk landscape for systems that depend on satellite-based PNT.

Heads of cybersecurity and information security will also find it a useful guide to a class of threat that is often excluded from cybersecurity risk analysis, but which must increasingly be viewed as part of the overall threat landscape.

Coming next: How to establish a test methodology for resilient PNT

As critical systems become more dependent on PNT sensors, understanding the resilience of those sensor-based systems is becoming essential. That not only means understanding the system’s ability to resist threats (its robustness), but also its ability to recover from an attack in which its ability to function has been compromised.

The emerging technical standards will define what resilience looks like in PNT systems, but establishing a test methodology for measuring system resilience will be extremely challenging. In the third webinar in our series, Spirent’s Aleksander Gorkowienko and I will set out the considerations involved in establishing a test methodology for resilient PNT, and provide some practical guidance for those who want to prepare now for the new standards.

The Implementing Resilient PNT in the Real World webinar series is now available on demand.




Ajay Vemuru

Director of PNT Simulation, Spirent Communications

Ajay Vemuru is Director of PNT Simulation at Spirent Communications. With over a decade of experience in location technology, Ajay’s work enables Spirent to acquire fresh insights, and make better decisions, accelerating customer developments in a range of emerging markets. Before Spirent, Ajay worked as a software engineer and research engineer at two of the leading semiconductor companies in Silicon Valley. Ajay has chaired technical sessions and hosted panel discussions at various industry conferences and seminars. Ajay holds a master’s degree in electrical engineering from Ohio University.